Composite ringer circuits



Nf. 3o, 1926.

H. W.ONE|LL COMPOSITE RINGER CIRCUITS Filed oot. 22, 1924 2 sheets-shew*b I 2N Www f @2 ill. rhuWJr r 1w l I r*www :mi l vm Nov. 30 1926.

H. W. ONEILL COMPOSITE RINGEH CIRCUITS 2 Sheets-Sheet 2 Filed oct. 22. 1924 Patented Nov. 30, `.19226.

UNlTED STATES vPATENT OFCE.

HENRY W. ONEILL, OF ELMI'IURST, NEVI YORK, ASSIGNOR TO WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEVI YORK.

COMPOSITE RINGER CIRCUITS.

Application led October 22, 1924.

This invention relates to composite ringer sets for relaying low frequency currents in to currents of high frequency and vice versa.

5 Composite ringer sets are quite generally interposed between a line and a switclr board on composited, repeated and other imilar line circuits, and serve to prevent low frequency signaling or ringing` currents M from reaching telegraph apparatus on composited circuits, and also to apply current at higher frequencies to telephone circuits in yorder that the current may traverse the telephone circuits without excessive attenuation. A standard type of composite ringer set now in general use is adapted to relay the usual switchboard ringing current of 16 or cycles per second to current at 135 cycles L second at the opposite or line side oil the set while inversely 135 cyclel current incoming at the line side of the set is relayed to 16 or 20 cycle current at the switch board side of the set.

Heretoi'ore it has been the practice to employ sources of alternating current which comprise equipment or units separa-te and distinct from the composite ringer sets themselves. For example, for ringing in one direction, the application of current from a 16 or 20 cycle source etfects responel te relays to switch the line circuit from the switchboard circuit to a source of 135 cycle current while tor signaling in the opiposite direction, current from a 135 cycle source eilects the response of other relays to switch the switchboard line from the eX- ternal line to a source of 16 or 2O cycle current.

lli/lith the composite sets as hereinbefore 'described dependent upon separate sources ot ringing current at the sets, it has not been possible to employ composite ringers except where such separate sources ot current are available. Thus, the use of such has been limited to such points where the traffic load is heavy enough to warrant the installation ot ringing generators. In accordance with the present invention, it is proposed to dispense with the separate sources ot current and to provide that relays may serve as vibrators to eii'ect the generation oi alternating current at proper frequencies ior carrying out the necessary signalinv' operations. The composite set is Serial No. 745,085.

thus rendered complete within itself and enables the use of the set at any isolated point or at points where, due to lower traiiic loads during the night, Sundays or at other times, itbecomes inadvisabl'e to maintain the power equipment in continuous operation.

It is the object of the present invention to provide a composite ringer set which shall be complete within itself, independent of outside ringing current and economical to install and operate.

The object of the linvention is attained through the employment of a vibrator relay of a type which short-circuits its own windings. Vibrators of this type are free from contact chatter and substantially unaffected by current overloads, have little or no tendency to spark at contacts, are easily adjusted and have large energy output as distinguished from vibrators et the inten rupter type which have heretofore been proposed. rihe vibrator relay is arranged to be common to a plurality or composite sets so that a single relay may serve as a means for generating signaling current for all or a part of the composite sets ot a switching station.

lt is believed that the invention will best be understood from a consideration of the drawings and the followinev detailed description thereof.

Fig. 1 shows one oic a plurality of composite ringer sets and a vibrator relay which is arranged common to the plurality of sets and arranged to serve the sets in groups.

Fig. 2 taken in connection with that portion of Fig. 1 above the dot and dash lines shows a modification in which the common vibrator relay is inductivelv coupled to the several composite sets which it serves.

Fig. 3 when talren in connection with that portion of Fig. 1 to the lett ot the dot and dash line, is a further modii'ication showing a dinf'erent manner of associating a common vibrat ry relay with several composite sets `of the repeating coil type.

Fig. 1lshows a composite set with a polarized relay which serves as both a responsive device and a transmitting device and circuits for rendering the polarized relay, whe serving asv a transmitting device, control lable by a master vibrator which is common to a plurality of composite sets.

Fig. 5, when taken in connection with that the windings O nefs 19 and 20. In emglcymg sew'- che dot and p0 led 'form oi ehe C11-- portion of ip'. 4. tQthe left of dash line, 511011321 moc transformer', inversely wound to winding 41,

thence through the winding of relay 21 to battery. The response of relay 21 closes a short circuit about itself establishing full potential across the terminals of winding 42. lilith winding 42 wound with more ainpere turns than winding 41, the magnetic effect produced by winding 42 overbalances that produced by winding 41 and a second half wave of opposite polarity rises in the upper winding 43 and is transmitted to the line 1 2. On the collapse of energy in the winding of relay 21 due to the closure of its contacts, release of the armature and operation of its contacts effects a substantial cessation of the current in the transformer winding 42 as the resistance of relay 21 is high. The current still present in the winding 41 of the transformer now neutralizes the residual magnetization and causes flux to build up in the first or opposite polarity direction. rlhis causes the second half wave of induced current to fall and be followed by rise of a half wave in the opposite direction. VSuch cycle of changes continue in phase with the frequency of vibrator 21 whose armature is tuned to a natural period of 135 cycles and whose winding is shunted by a resistance 24 and condenser 23 in series for the purpose of preventing sparkingat the contacts of the relay and for providing a resonating path for the relay.

As indicated at 2G, the transformer 22 may be provided with an electrostatic shield connected to ground whereby the winding 43 may be isolated relative to mutual capacity effects from the windings 41 and 42. In the general use of the system, however, this shielding may be omitted.

Referring to Fig, 3 taken in connection with that portion of Fig. 1 to the left of the dot and dash line, a common Vibrator tuned to operate at 135 cycles frequency is shown in the enclosed rectangle for supplying 135 cycle signaling current to a plurality of composite sets. In the composite set disclosed, a repeating coil of the usual type is employed to effect an inductive coupling between the switchboard and outgoing line conductors.

When 2O cycle signaling current is applied at the switchboard to the line 3 4, the current flows over conductor 3, the back contact of relay @the upper left winding of repeating coil 50, relay 9, condenser 13, the lower left winding of coil 50, the lower back contact of relay 7 to conductor 4. Relay 9 enerfizes, in turn establishing an operating circuit for relays 8 and 14. These relays function in identically the same manner as previously described in connection with the circuit of Fig. 1 to hold relay 10 operated, disconnect the limbs of line 1 2 from the right windings of repeating coil 50 and connect them to the upper winding of transformer 25 and to start the commonv vibrator relay 21 into operation. Upon the initial energization of relay 14 with relay 21 deenergized, a circuit is closed from ground through the winding 44 of transformer 25 and winding of relay 21 in parallel therewith, thence through the winding 45 of the transformer to battery. lf the two windings and 45 are wound to diderentially balance each other under these conditions, no current is induced in the upper winding of the transformer 25. Since relay 21 energizes in this circuit, it shunts its own winding thereby causing an increased flow of current through the winding 44 overbalancing the effect of winding 45. Current is thereby induced in the upper winding of the transform r and flows to the line 1 2 as a half wave of one polarity. As soon as relay 21 shunts its winding, however, it deenergizes, again restoring the windings 44 and 45 to their initial condition whereby current is induced in the upper winding of the transformer and flows as a half wave of the opposite polarity to the line 1 2. Thus, as relay 21 vibrates at a frequencyof 135 cycles, to which its reed armature is tuned, a signaling current is transmitted to line 1 2 in phase with the vibrator-y operation of relay 21. A resistance 24 and condenser 23 connected from the circuit of relay 21 to ground serve to prevent sparking at the contacts of relay 21.

If desired, the windings 44 and 45 of transformer 25 may be proportioned similarly to the windings 41 and 42 of transformer 22 (Fig. 2), the windino' 44 having a greater number of ampere turns than winding 45. lVith windings wound in this manner, when relay 14 energizes, the current flowing through the winding 44 in series with winding/45 will cause the winding 44 to overbalance the winding 45 and produce a flux which will cause current of one polarity to flow from the upper winding of transformer 25 to the line 1 2. At the same instant, relay 21 energizes short circuiting its own winding and the winding 44 thereby withdrawing the overbalancing effect of winding 44, whereby winding 45 is enabled to produce current in the upper winding of transformer 25m the opposite polarity direction. This cycle of operations is then repeated in phase with the vibration of relay 21.

When a signal is incoming to the comp'osite set from line 1 2, 135 cycle signaling current flows from conductor 1 over the upper back contact of relay 3, through the upper right winding of repeating coil 50, both windings of relay 6, the lower right winding of repeating coil 50., the lower baci; contact of relay 8, back oi'er conductor 2. causing 5 the energization of relay 6 which is tuned to respond to current of 135 cycles frequency. Relay 6 in operating opens the circuit of relay 10 thereby causing the energiaation of relay 7 and the application of low frequencyr current from source 5 to the switchboard line 3 4.

ln Fig. l, relay 6 is of the same type as similar relays shown in the modiiications previously described and is under the control of a master Vibrator 36 of the saine type. As indicated by the multiple connections, the master vibrator relay 36 is coninion to a plurality ot composite sets. llllhen low frequency signaling current is applied at the switchboard to the conductors of line t"ln-fl, the relay 9 which is bridged across the conductors 3-d through the retardation coil 12 and condenser 13, through the back contacts of relay 7, responds and establishes au obvious circuit ior relays 3 and 1e. Relay 8 upon energizing disconnects the talking conductors of the composset Jtroni conductors 1 and 2 ot the outline and bridges the right winding isl'orincr 31 across conductor 1 and 2 through condenser ln addition, relay 3 opens the circuit ot relay 27 to prevent its 'false operation at this time and prepares a circuit `tor i Relay 11i upon energizcloscs an 1ceiuting circuit ttor the inaster vibrator relay 36 extending troni battery threunii both windings oit relay 36 to `around at the lower contact oi" relay lll. The vibrator relay thereupon a tracts its armature placing short circuit about its own windiAQ whereupon it deenergizes and then continues to repeat this cycle ot operations so longas relay 14 remains energized. lllith relays 6 and 14e both ener- 1 'l a circuit is closed *for relay 6 extendrein battery through the middle upper Contact ot relay 1li, both windings of 6 to ground at t ie upper alternate con- 't relay 3. Relay 6 upon energizing in ci 1cuit closes a circuit from ground at contacts through the upper front contact y 3, the lett winding oi' transformer o .cattery through the innermost upper ontact of relay 14e. The surge ot thus produced in the le'lt winding ot .sloi'iner 31 is induced in the right winding` thereof and flows as a half wave of alternating current out over the line 1 2. llhen relay 36 shunts its windings, a shunt is established thereby around the windings el relay 6, this shunt extending from the ground at the uppermost Contact of relay 3 through the windings ot relay 6, the upper middle 'front Contact o't' relay lll, the contacts of relay 36 to ground at the lower contactot relay lil. rl"his shunt causes the de- 'ation of relay 6 andthe opening oi' the circuit through the left winding` or 31 whereby current is induced Y Y right wind et transformer 31 to produce a halt wave ot alternating current LI o the opposite polarity over line conductors 1-2. this manner, as relay 36 yibrates,

alternaan@ current is transmitted to the line 1,eos,522

1 2 in phase with the ribratory action of relay 36. Since relay 36 is tuned to operate at a frequency of 135 cycles, the outgoing signaling current will be ot 135 cycles. To absorb the surges vtroni the transformer 31 and thereby protect the contacts ol relay 6, a. condenser is connected in shunt ot the winding ol transfo-"incr 3i over the innermost upper front Contact ot relay 1l. rhis condenser also serves to increase the output and improve the wave iiorm 01" the j current produced. lllhen a signaling current 135 cycles irequency is incoming` over the line 1-2 with relays S and l-/l both deenecimd. frzurreut llows troni condu denser 32, the right wc -l l the innermost e i., ugpei e i lay lethe left winding of trans 'ormer 31, the

uppermost back Contact ot relay 8, both windings oit relay 6, middle upper back contact of relay 1e, middle back contact of relay 3 to conductor 2. Relay 6 en-ergizes in this circuit and at its front contact closes a circuit roin ground over the lower back contact of relay 3, resistances 23 and 29, winding of relay 27 to battery. rlhis energization ot relay 6 at the rate ol 135 cycles producing an intermittent closure of the circuit of relay 27 produces a local current in the circuit comprising the winding of relay 27, resistance 28 and condenser 36 which is sui'llcient to maintain relay 27 energized. Relay 27 operates, shunting the windingot relay 10 which upon deenergizing operates relay 7. Relay 7 upon energizing disconnects the talkin@` conductors of the set Ytroni the :D switchboard line 3-4l and connects the source of low frequency ringing current 5 with the conductors ci line 3-4l. Condenser 30 in conjunction with resistance 28 in shuntot the windiiur of relay 27 eliects a steady energization or relay 27 during the geriet that relay 6 is operating in response to incoming signaling current. The condenser 32 in the energizing circuit of relay 6 serves for effecting a condition oiE series resonance for relay 6 while the condenser 34 which is connected in shunt ot the winding of relay 6 through the uppermost bacl; contact of relay 1lei'lects parallel resonance for relay 6 with respect current at 135 cycles.

Fig. 5 taken in conne tion of Ll t of the dot and dash line shows a inodih'c-ation einploying'a master y water relay 35 common n with that porto a plurality composite ets. For an out-going signal ring' g c :eI t applied over connects the right winding of transformer 31 to the limbs of line 1-2 and in conjunction with relay 14 prepares energizing circuits for relay 6 and 35. The energizing circuit of relay 35 may be traced from ground through the winding of this relay, resistance 40, lower front contact of relay 14 to battery. The circuit of relay 6 may at this time be traced from battery through the lower front contact of relay 14, the upper front contacts of this relay, the windings of relay 6, the lowermost front contact of relay 8, to ground through the winding of relay 35. The winding of relay 35, however, is lof such resistance that relay 6 which is connected in parallel with resistance 40 does not receive suliicient current to cause its operation at this time. Relay 14 in addition to the functions above described, opens the circuit of relay 27 at the lower back Contact of relay 14 to prevent its false operation when relay 6 energizes as later described.

As soon as vibrator relay 35 energizes, it closes a circuit about its own winding thereby reducing the resistance in the circuit of relay 6 to such an extent that relay 6 operates. Upon the energization of relay 6 a circuit is closed from ground through the left winding of transformer 31, contacts of relay 6, upper front contacts of relay 14, lower front contact of relay 14 to battery. The surge of current in the left winding of transformer 31 induces a half cycle of alternating current in the right winding of transformer 31 which flows out over line 1-2. As soon as vibrator relay 35 short circuits its own winding it becomes deenergized, again introducing the resistance ot' its own winding in the operating circuit of relay 6 thereby causing relay 6 to deenergize. The deenergization of relay 6 opens the circuit through the left winding of transformer 31 thereby inducing a half wave of alternating current in the right winding of transformer 31 which flows in the opposite direction Vover line 1-2. Vibrator relay 35 continues to operate in the cycle above described at a frequency of 135 cycles to which its reed armature is tuned, thereby producing an alternating current of the saine frequency in the line 1-2. The condenser 33 connected in shunt of the left winding of transformer 31 effects a reduction of the sparking at the contacts of relay 6 and tends to smooth out the wave form of the alternating current transmitted over line 1 2.

For an incoming signal with relays 8 and 14 both deenergized, alternating current of 165 cycles `frequency flows from conductor 1 over the upper back contact of relay 8, impedance coil 38, condenser 39, lowermost back contact of relay 8, windings of relay 6, upper back contact of relay 14, middle back contact of relay 8 to conductor 2. Relay 6 in responding to this alternating current closes a circuit for relay 27 extending from battery at the lower back contact of relay 14 through the winding of relay 27, resistances 28 and 29, contacts of relay 6 to ground through the left winding of transformer 31. Relay 27 upon energizing causes the application of low frequency ringing current from the source 5 to the switchboard line 3-4 in the manner described in connection with Fig. 4. The condenser 39 connected serially in the circuit of relay 6 efects series resonance forthe relay 6 and condenser 37 which is connected in parallel with the windings of relay 6, etlects parallel resonance relative to the control of relay 6 at 135 cycles frequency.

During the reception of incoming signals from the line 1-2, t-he master vibrator relay 35 is functionless with respect to the particular composite set which is receiving the incoming signals but may be at the time functioning to produce outgoing signals in connection with other composite sets.

lthat is claimed is:

1. ln a telephone exchange system, a plurality of lines and means for applying signaling current to said lines comprising a vibratory relay individual to each of said lines, means for inductively associating said relays with the lines to which they are individual, and a master vibrator relay common to said relays and controlling the vibratory operation thereof, said master relay having short circuiting contacts for causing its own l'ibratory operation.

2. In a telephone exchange system, a plurality of lines, and means for applying signaling current to said lines comprising a vibratory relay individual to each of said lines, means for inductively associating said relays with the lines to which they are individual, and a master vibrator relay common to said relays, said master relay having short circuiting contacts for controlling its own and the vibratory operation of said other relays.

3. ln a telephone exchange system, a plu-v rality of lines, a relay individual to each of said lines responsive to `signaling current of a predetermined character incoming or outgoing over said lines, means for inductively associating said relays with the lines to which they are individual, and means comprising a master vibrator relay common to said relays and controlling the vibratory operation thereof, said master relay having short circuiting contacts for causing its own vibratory operation and said first relays when functioning under the control of said master relay cooperating with said inductive means to generate and apply signaling current of said predetermined character to said lines.

lll() ll. n a telephone exchange system, a plurality of lines, a relay individual to each of said lines responsive to signaling current of a predetermined frequency incoming or outgoing over said lines, means for indue tively associating said relays with the lines to which they are individual, and means comprising a master vibrator relay common to said relays and controlling the vihratory operation thereof, said master relay having short circuiting contacts for causing its own vihratory peration and said first relays When functioning under the control of said master relay cooperating with said inductive means to generate and apply signaling current of said predetermined frequency to said lines, and means for resonating said relays to said predetermined frequency.

ln a telephone exchange system, a plurality of lines, and means for applying signaling current to said lines comprising a vibrator relay and a transformer individual to each of said lines, circuits extending through one Winding of each of said transformers and the contacts of the associated relay, means for connecting the other Windings of said transformers With the associated lines, and a master vibrator relay common to said relays for controlling the vibratory operation thereof.

6. ln a telephone exchange system, a plurality of lines, each divided into a irst and a second section, means associated with each line responsive to signaling current of a eertain character incoming over the first section thereof, means individual to each of said lines responsive to signals of another character incoming over tie second section of each of said lines for controlling the apglication of signaling current of certain character to the first sections of said lines, and means common to said lines for controlling the generation and transmission of signaling current of said other character over the .second section of each of said lines, said last named means losing under the cont-rol of said first named means andL comprising a vibrator relay.

7. ln a teleohone exchange system, a piurality of lines each divided into a iirst and i yooit-.tod uit each a secenc section, means ass 't line responsive to signaling current t c yre* io a e ain character incoming over the sec- `ron thereof, means individual to each of character incoming over the second section of each of said lines for controlling the application of signaling current of said certain character to the first sections of said lines, and means commen te said lines cooperating with said second means for generating and transmitting signaling current. cf said second character over the second sections of said lines, said last named means oeing controlled by said first named means and comprising a vibratory relay.

ln 1Jitness whereof, l hereunto subscribe my name this 16th day of @ct-ober A. 1924.

HENRY lV. GNEILL.

-aid lines responsive to signals of a second 

